Air-heater for furnaces



Patented Aug. I6, I898. W. STUBBLEBINE.

AIR HEATER FOB FURNACES.

(Application filed Jan. 26. 1897.)

2 Sheets-$heet I.

(No Model.)

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Patented Aug. I6, I898.

(Application filed Jan. 1 I

2 Sheets-Sheet 2.

Inflrafir m aJfiJZ&5zze W STUBBLEBINE AIR HEATER FOR FURNACES.

(No Model.)

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WVILLIAM STUBBLEBINE, OF BETHLEHEM, PENNSYLVANIA.

AIR-HEATER EQR FURNACES.

SPECIFlCATION forming art of Letters Patent No. 609,306, dated August 16, 1898'.

' Application filed January 26,1897; Serial n. 620,816. (No model.)

.lowing to be a full, clear, and exact description of the invention, such as will enable others skilled in the artto which it appertains to make and use thesame.

My invention relates toimprovements in the means for heating the airblast in reverberatory and regenerative furnaces especially adapted to metallurgical operations; and the object that I have in view is to provide a simple arrangement to utilize the waste gases from the working chamber for economically heating the large volumes of air required to be forced into, the furnace for properly treating the metal in the working chamber.

The first part of my invention relates to the novel construction and arrangement of the furnace in a way to utilize parts of the furnace structure in connection with air-blast heaters situated on the roof of the furnace. That part of the roof over the working chamber adjacent to the stack is arched or carried downward and provided with'a multiplicity of inclined ports for the escape of the gases and heat from the working chamber, and over this arched or curved part of the roof is erected a preliminary blast-heating chamber, which contains aheating medium, such as aheavy metallic plate or fire-brick, that divides and partitions off the preliminary heating-chamber into upper and lower compartments, in

the lower of which chambers are delivered the Waste heat and gases from the working chamher, from whence they pass through a port or neck into the stack or uptake of the furnace. The upper compartment of this preliminary heating-chamber has a cold-blast pipe conneoted thereto, in which the air is heated and expanded before it is conducted through a hot-blast pipe that leads to a delivery-chamber situated onthe roof of the furnace nearly over the bridge-wall, from which deliverychamber the hot blast passes into the working chamber through ports provided in the roof of the furnace. 1 i

The second part of my invention relates to specification, and in which-- Figure 1 is a vertical longitudinal sectional this middle circMating-compartment, which connects through passages with the working chamber and the stack, free and unobstructed by'the air-pipes, and these airpipes or lines are built in or embedded into the walls of the chamber and have elbows at their ends which are connected to the upper and 10mg aircompartments, whereby the furnace-walls se'rve'lto protect the air-heatingpipesfrom direct contact with and the deterioratingam tion of thehot gases from the Working cham her; and the invention further consists in the novel construction and arrangement of devices which will be hereinafter'fully described and claimed. a

; To enable others to understand my invention, I haveillustrate'd the same in the accompanying drawings, forming a part of this elevation of a furnace embodying my invention, the plane of the section being indicated by the dotted line 1 10f Fig. 2. Fig.2 is a sectional plan View of the furnace, the plane of section being taken on theirregular line 2 2 of Fig.1. Fig. 3 is a vertical transverse sectional elevation through the rearor stack wall of the furnace on the plane indicated by the dotted line 3 3 of Fig. 1. Fig. 4: is a vertical transverse sectional View on the line 4: 4: of Fig. 1. a

Like letters of reference denote corresponding parts in all the figures of the drawings.

I will now proceed to describe the embodiment of my invention shown by the drawings, in which i i A B designate the working and combustion chambers, respectively, with the intervening fire-brick bridge-wall a.

C is the stack or uptake, and i) is the bed of the working chamber. The working chamber has the usual working doors a, and in the combustion-chamber is provided the grate b, an air-blast inlet 1), and the usual doors.

- E is the roof of the furnace, which lies in a substantially horizontal plane over the combustion-chamber and over the major portion of the working chamber; but that part of the roof adjacent to the stack or uptake 0 is curved 01' extended in a downward direction to produce the arch E. Over this arched end of the roof is erected the heating-chamber F, preferably built up of brick or masonry and havingits rear end formed by the rear or stack wall of the furnace. The top of this chamber F is of brick, within which is a heavy metallic plate f, and said chamber F is divided into two parts F F by a horizontal partition G, which may be of brick or a heavy metallic plate, the latter being preferred because it is adapted to be highly heated. This partition G lies in the plane of the roof E and over the arch E, and the chamber F is thus formed by the arch, the rear stack wall, and the partition G. This lower chamber is a gas and heat circulating chamber, to which are admitted the waste gases and heat from the working chamber through the series or multiplicity of ports 6, which are provided in the arch E, as shown by Figs. 1 and 2. From this circulating-chamber F leads the port or neck g, which extends to the uptake, and thus the waste heat and gases from the working chamber are caused to pass through the ports 6, then circulate in the chamber F, then pass through the neck or port g, and thence escape into the uptake. The heavy metallic plates f G in the chamber F and the walls of the chamber itself become highly heated by the hot waste gases and heat from the working chamber, and thus the cold blast supplied from the pipe His heated in the chamber F preliminary to passing through the hot-blast pipe I into the delivery-chamber J.

The upper chamber F has its top and bottom formed by the metallic plates f G, and said chamber forms an airblastheating chamber for the cold blast which is delivered thereto by the cold-blast pipe G, having a suitable regulating-valve. From the side of this blast-chamber F leads the hot-blast pipe I, which extends horizontally above the roof E to the delivery-chamber J. This chamber J is of brick or metal, erected on the roof at a suitable point over the Working chamber A; but I prefer to place it nearly over the bridge-wall a, as shown by Fig. 1. Usually this chamber J is of fire-brick, and its roof is lined with a heavy metallic heating-platej, and in the roof E, within the limits of the walls of the chamber, are provided a large number of ports or openings J, through which the hot blast of air is designed to pass into the working chamber A.

It will be seen that I have provided an improved heating arrangement in which the "Figs. 1, 2, and 3 of the drawings.

waste gases from the working chamber are utilized to economically heat to a high degree the air from a cold-blast pipe, the hot blast being delivered into the front part of the working chamber to commingle with the heat and gas passing over the bridge-wall. It is also necessary to feed hot air into the working chamber at intervals along the length of the latter, and to the accomplishment of this end in an economical manner the rear wall of the furnace is built up to provide the blast-heatin g chambers shown by These blast-heating chambers are provided in the rear wall on opposite sides of the stack or uptake, and each chamber is divided by heavy metallic plates or fire-brick partitions 7c it into the central circulating-chamber K and the air-blast chambers L L. The circulating-chambers K are free or unobstructed by pipes, flues, checker-work, or other heating medium, and they are connected by intakepassages K with the working chamberAand by outlet passages K with the uptake, whereby a part of the waste heat and gases from the working chamber are caused to pass through the passages K into the chamber K to circulate therein and heat up the said chambers and to thence escape through the passages K into the uptake.

The cold blast is delivered by the valved pipe M into the lower or blast chamber L, and from thence is conducted to the upper hot-air chamber L through the metallic heating pipes or fiues N. The pipes are not situated in the circulating-chambers K and exposed to the direct action of the highlyheated gases from the working chamber; but in order to protect the large number of metallic pipes or flues which are required to properly conduct the blast from chamber L to chamber L, I embed the metallic pipes in the walls of the chambers.

When the rear wall of the furnace is in the course of erection, I build the brickwork around the metallic pipes or fines to form a protective casing for the same against the direct action of the highly-heated gases. The ends of the pipes or fines N are elbow-shaped or bent to open into the blast-chamber L and the hot-air chamber L, and these embedded pipes N are heated to such an extent as to make the air hot as it passes through the pipes from the chamber L to the chamber L. In the side walls of the furnace, on opposite sides of the working chamber A, are provided the delivery pipes or flues O O, the rear ends of which are connected with or open into the hot-air chambers L. These pipes or fines O O are provided on their inner sides with a number of perforations or passages 0, which extend. inwardly through the furnace-walls and open into the working chamber A, so as to discharge hot air therein at suitable intervals along both sides of the furnace.

No claim is herein made to the structure of a furnace in which the preliminary metal heating-chambers are made elements in the structure of the stack-wall, substantially as represented by Figs. 5 and 6 of the drawings, as the same forms the subject-matter of a separate application filed by me on the 9th day day of March, 1898, Serial No. 673,215.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a metallurgical furnace, the com bination with a working chamber having a bridgewall, and a stack or uptake, of isolated heating-chambers situated on the roof of said working chamber, one heating-chamber lying adjacent to the uptake and the other arranged substantially over the bridge-wall, each heating-chamber containing within its walls a heating medium and said heating-chambers communicating with the Working chamber by series of ports in the roof thereof, and a blast pipe connected to said heating-chambers, as and for the purposes described.

2. In a metallurgical furnace, the combination with a stack or uptake, and a working chamber having a bridge-wall, of heatingchambers each divided by a transverse heating medium into upper and lower compartments and said lower compartments communicating directly with the working chamber through series of ports in the roof thereof, said heating-chambers being arranged one near the stack and the other substantially over the bridge-wall in the working chamber, and a blast-pipe connected to the heating chambers to communicate with the upper compartments thereof only, substantially as and for the purposes described.

3. In a metallurgical furnace, the combination with a stack or uptake, and a working chamber having a bridgewall at one end, of the heating-chambers situated on the roof of said working chamber, one adjacent to the stack and the other substantially over the bridge-wall, and each communicating with the working chamber through ports in the roof thereof, perforated metallic plates arranged within said heating-chambers and forming the heating mediums therein, and blast'pipes connected to said heating-chambers, as and for the purposes described.

4. A furnace having its rear stack-wall provided with a circulating-compartment which is free from, or unobstructed by, pipes or checker-work and also provided with a blast-chamber and with a hot-air chamber, combined with air-heating pipes embedded in the stack-wall adjacent to said chambers and connected at their ends with the blastchamber and hot-air chamber, a working chamber connected by a port to said circulating-compartment, an uptake communicating with said circulating-compartment, and oft-bearing pipes or lines connected to the upper hot-air compartment, as and for the purposes described.

5. The combination, in a furnace, of the roof arched adjacent to the stack or uptake and provided in said arched portion with transverse gas-ports, the uptake or stack, the heating-chamber over the arched part of the root" and divided by a transverse partition into two chambers, one of which compartments is connected with the working chamber and the uptake and the other compartment forming an isolated blast-compartment, a blast pipe or pipes connected to the blastcompartment of said heating-chamber, and a port or neck between the uptake and the lower compartment of the heating-chamber, substantially as described.

6. The combination with astack or uptake, and a working chamber, of the heating-chamber divided into upper and lower compart ments, the ports in the roof of the working chamber and connecting said working chamber directly to the lower compartment of the heating-chamber, a port or neck which connects said lower compartment of the heatingchamber with the stack or uptake, and blastpipes connected to the upper compartment of the heating-chamber, substantially as described.

7. The combination with a working chamber, and an uptake of a metallurgical fur nace, of the horizontally-divided heatingchamber F, ports which connect one compartment F of the heating chamber with the working chamber, a port or neck connecting the stack and the compartmentl of the heating-chamber, blast-pipes connected to the isolated compartment F of the heating-chamber, another non-divided heating=chamber J connected to the working chamber, and the.

blast-pipes between the two chambers F, J, substantially asdescribed.

8. The combination with a working chamber and an uptake, of a heating-chamber situated on the roof of the working chamber and provided with a partition which divides said chamber into two compartments, the lower of,

which compartments communicates directly by ports with the working chamber and the stack, to insure circulation through said cham ber of the waste heat and gases on the way from the working chamber to the stack, another chamber situated at one side of the firstnamed chamber and over the working chamber, communicating directly therewith by ports in the roof of the same, and a blast-pipe connecting the upper compartment of the first-named chamber with said last-named chamber, substantially as described.

9. The combination with an uptake, and a working chamber, of the roof having the arch E adjacent to said uptake and provided with ports 6 which extend directly through the arched portion of said roof, the heating-chamber F having an intermediate partition which divides the heating-chamber into upper and lower compartments, the said lower compartment being in a plane substantially horizontally between the working chamber and the stack and communicating With said chamber nected to said first-named heating-chamber, 10 and stack directly by the ports eand the neck, substantially as described.

respectively, another chambersituated at one In testimony whereof I affiX my signature side of the chamber F and on the roof of the in presence of two Witnesses.

5 workin chamber communicatim directly with m; latter through ports in said roof, at WILLIAM STUBBLEBINE' hot-blast pipe connected to the upper com- Witnesses: partment of the chamber F and with the other FRANK WENZEL,

heating-chamber, and a cold-blast pipe con- GEO. L. BAUM. 

